Is this tap legal?

[jim dungar]

It looks like the conductors are more than 50 Yeats old. There is a substantial amount of dirt on the lugs
What edition of the NEC an UL891 should be applied?

The OEM probably used spacing that would correspond to 600V breaker fingers. Isnt 480 V spacing less than 1 through the air?

 

[Tainted]

From UL:

Panelboards and deadfront switchboards are not Listed to have their busbars tapped unless there are existing holes in the busbars marked with the word “Tap” adjacent to the holes. Other holes in the busbar that are not marked with the word “Tap” are intended for the connection of overcurrent devices, other devices as identified by the product markings and in the installation instructions, or other uses identified by the manufacturer.

I've seen an inspector look at a tap once and didn't say anything, I guess he didn't care and it depends on who looks at it. The tap location didn't have the word in it

Do we know if it's a service bus or a feeder?

feeder

 

[brycenesbitt]

I've seen an inspector look at a tap once

Performing is important, perhaps even more than conforming.